This invention relates to an electrical distribution system of the kind comprising a length of hollow conduit enclosing a plurality of continuous electrical conductors, and an aperture in one wall of the conduit through which access to the conductors can be achieved by means of the appropriate contact plug.
An electrical distribution system of this kind is described and claimed in U.S. Pat. No. 4,243,284. In this system, the conduit is formed with a longitudinally-extending entry aperture in one wall through which the contact plug can be inserted; rotation of the plug brings its contact pins into electrical contact with the continuous conductors enclosed within the conduit. A safety arrangement is provided, comprising a series of internal safety doors disposed within the conduit, which are biassed into normally closed positions in which they close off that part of the conduit containing the conductors from the entry aperture. The action of pushing a contact plug into the aperture opens one of these safety doors and enables the plug to be rotated into a position in which the contact pins make electrical contact with the conductors. The design of this safety arrangement makes access to the conductors by means other than the correct plug very difficult.
The present invention provides a modified electrical distribution system of this kind, which has certain advantages in manufacture, and which enables various alternative safety arrangements to be used.